ENGLEWOOD, Colo. -- It's not secret the Denver Broncos want, and need, a third wheel in the team's passing game.

Sure, they like that wide receivers Demaryius Thomas and Emmanuel Sanders are among the most productive players at the position in the league. They like that Thomas and Sanders combined for 169 catches last season.

They don't like that defenses loaded up so often on the two outside targets -- and it was especially effective in the red zone where each was held to five touchdown catches in 2016 -- because they didn't believe Denver had anybody else to really worry about.

Which is why, in his third mock draft of the pre-draft season, ESPN's Mel Kiper Jr. gave the Broncos Miami tight end David Njoku as the pick at No. 20. In his previous two mock drafts Kiper had put Utah tackle Garett Bolles there as the selection.

Certainly, Njoku's athleticism sets him apart -- he averaged 16.2 and 17.2 yards per catch respectively in his two seasons with the Hurricanes -- and he was a national champion in the high jump as a prep athlete with a jump of 6-11.

As a player, however, he is still a work-in-progress. He has plenty of room to grow as a blocker and has too many drops of in-frame throws for a player of his talent level. But as a receiver he would be a match-up problem as a rookie because of his speed and explosiveness.

"I think wherever I go, I can definitely bring speed," Njoku said at the combine. "I'm willing to block anywhere, attached or detached. Speed. And a lot of fun."

In the Hurricanes' game against Duke this past season, for example, Njoku had two catches which went for 76- and 58-yard touchdowns.

The Broncos didn't have a tight end with more than 22 catches -- Virgil Green finished with those 22 receptions -- and Green was tied for the lead in the position group with just one touchdown catch.